Title: Preliminary Studies on the Influence of Nano-cellulose and Nano-alumina Fibers on UHPFRC
Author(s): Marta Roig-Flores, Eduardo J. Mezquida-Alcaraz, Ariel A. Bretón-Rodríguez, Juan Navarro-Gregori and Pedro Serna
Publication: Symposium Paper
Appears on pages(s): 351-369
Keywords: aluminum oxide nanofibers, energy, nanocellulose, nanomaterials, UHPFRC
Ultra-High-Performance Fiber-Reinforced Concrete (UHPFRC) is a type of concrete with superior mechanical and durability properties, which might be improved even further with the addition of nano-materials. This work studies the influence of adding nano-additions to two UHPFRCs with compressive strength around 150MPa (21755 psi), with and without crystalline admixtures. Two nano-materials were considered: cellulose nano-crystals (4-5 nm diameter, 50–500 nm length, 0.157-0.197 μin diameter, 1.97-19.7 μin length); in a dosage up to 0.15% by the cement weight; and aluminum oxide nanofibers (diameter 4-11nm, length 100-900nm, 0.157-0.433 μin diameter, 3.94-35.4 μin length) in a dosage of 0.25% by the cement weight. Water content of the mixes with nanomaterials was modified to maintain workability in a similar range aiming to maintain the self-compacting behavior. The following properties were analyzed: workability, compressive strength, modulus of elasticity and tensile properties calculated through a simplified inverse analysis after performing four-point bending tests. The study considered the effect of using three levels of mixing energy to ensure a proper dispersion of all the components, and its effect in the aforementioned properties. The results show a potential effect of these nanomaterials as nanoreinforcement,
with slightly better ultimate strength and strain values for the higher energy level.